New arrest over UK migrant truck deaths

A man from Northern Ireland has been arrested by UK police investigating the deaths of 39 migrants whose bodies were found in a truck container in Essex.

The lorry where 39 people were found dead inside leaves Grays, Essex. Source: AAP

British police have arrested a 23-year old man from Northern Ireland as part of their inquiry into the deaths of 39 Vietnamese people found in the back of a truck near London.

"He was arrested on suspicion of conspiracy to traffic people and conspiracy to assist unlawful immigration and remains in custody," Essex Police said in a statement on Friday.

The man was arrested on a motorway in Beaconsfield, west of London, the statement said.

The victims - 31 males and eight women - were found in a truck container on an industrial estate in Grays, Essex, not far from docks on the River Thames, on 23 October.

The truck driver, who is also from Northern Ireland, has been charged with 39 counts of manslaughter, conspiracy to traffic people, and money laundering.

Nguyen Dinh Gia, father of Nguyen Dinh Luong, who is believed to be among the 39 people found dead. Source: AAP

A second man has been charged with the same offences and British authorities are trying to extradite him from Dublin.

Police have also been looking for two brothers from Northern Ireland.

Police in Vietnam have arrested 10 people there in connection with the deaths.